My friend made an examination if it is possible to upgrade the Dinah by installing BMW 801 engines. He found out they were much too heavy. So the airframe was on its limits. The space between the two crew members is also completely filled by the fuselage fuel tank, so there is no place for an internal bomb bay.

To break even and outreach the Mosquito, a considerable expansion of the airframe would have been necessary. I still think there were chances to achieve it.